More from WebMD

June 28, 2012 -- Teens who have more peer problems than normal are at higher risk of health problems as adults, Swedish researchers report.

They followed more than 800 Swedish teens from age 16 to 43. The researchers assessed peer problems as teens, asking teachers to weigh in. They followed the teens to see who developed a condition known as metabolic syndrome, which raises the risk of heart disease, stroke, and type 2 diabetes.

They found a link. ''Peer problems at a young age are correlated to an increased risk of metabolic syndrome in middle age," Urban Janlert, MD, PhD, professor of public health at Umea University, Sweden, tells WebMD.

"It's a moderate risk, I would say," Janlert says.

The new research ties in with other findings about the effects of so-called toxic stress in childhood and later health, says Benjamin Siegel, MD. Siegel is chairman of the American Academy of Pediatrics (AAP) committee on psychosocial aspects of child and family health.

The study is published online in PLoS One.

Teen Peer Problems and Adult Health: Study Details

Janlert's team asked the teachers of more than 1,000 teens to assess each student's isolation. Teachers also told how well a student was liked and how well they got along with school peers at age 16.

At ages 16 and 43, the men and women completed a questionnaire about their social circumstances, behaviors, and health.

At age 43, they had health exams. Measurements included:

Blood pressure

Blood glucose

Waist circumference

To be diagnosed with metabolic syndrome, three of five factors must be present:

Elevated blood pressure

Elevated blood sugar

Large waist (above 35 inches for women, 40 for men)

Low level of "good" or HDL cholesterol

Elevated level of triglycerides

The greater the teen peer problems, the higher the risk of metabolic syndrome at age 43, Janlert found.

As an example, he says, "if there is a 40% increase in peer problems compared to people who are assessed to have normal peer problems, there is a 36% increased risk of metabolic syndrome at age 43."

Overall, they estimated that 19% of the women and 34.5% of the men had metabolic syndrome. Janlert says they cannot prove cause and effect, only a link.

"We haven't shown that to take peer problems away will make the problems [in adulthood] disappear," he says.

The link may be indirect, he says, even though they took into account other factors that increase the risk for metabolic syndrome. The peer problems, for example, may reflect problems in the family that play out at school.

The link between teen peer problems and later ill health was slightly stronger for women. "I think social support is more important for women than for men," he says.

Second Opinion

The findings are no surprise, says pediatrician Michael Yogman, MD. Yogman is a member of the AAP's committee on psychosocial aspects of child and family health. He reviewed the findings for WebMD.

"We are now seeing increasing data about the crossover and intersection of environmental stress, which is referred to as toxic stress, and these long-term effects on metabolic and regulatory systems," he says.

"We think it has to do with the stress response, the fight-or-flight response," says Yogman, who is also chairman of the board of the Boston Children's Museum. "When that response is extreme in a sustained way, without any kind of support or buffer, it can reset blood pressure, sugar metabolism, fatty acid metabolism, very basic biological systems."

Siegel agrees. He says the link is probably tied with stress and the stress hormone cortisol, and their effects on the body.

"There is a difference between toxic stress, which is permanent and causes problems, and limited stress, which you can do something about," he says.

Teen Peer Problems: Tips for Parents

Parents can help their teens reduce peer problems and the stress it causes, the doctors say.

"The way to buffer stress is to be supportive," Yogman says. "If your child is isolated at school and doesn't have any friends, I think you need to intervene."

Parents should consider introducing their teens to activities they might enjoy, such as sports or music, he says. The goal is to improve their peer relations.

Communication is key, Siegel says. "Talk to your adolescents and see if you can be sensitive to the changes they are going through."

Be especially sensitive to those teens with weight problems, Siegel says. "Kids who are more obese go through more peer problems."